Thanks for your reply, I understand that I need integration to get the change in position. My problem is that my programming skill is really bad...
I have the firmware given in the tutorial, but I don't know how should I write the code based on the firmware to achieve it. Could you pls kindly help me on this?
The level of programming required to do what you're looking for is quite advanced. This is not your basic issue a call and get your coordinate type of thing. Basically, even if someone wrote custom code for you to calculate your position you still wouldn't be able to implement that information to do anything useful as that would also require a bunch of custom programming, and so on...
Here's a thread that may help you grasp the complexity of what you're asking for:http://arduino.cc/forum/index.php/topic,58048.0.html
If this is about your pay grade, you either need to work on your coding skills or hire someone to program for you.